crypto: use mr-tron/base58 for base58

Use more fast and reliable implementation. Add some tests for our wrappers,
deduplicate code in PublicKey.Adress(). Fixes #355.

go.mod

@@ -5,6 +5,7 @@ require (
 	github.com/go-redis/redis v6.10.2+incompatible
 	github.com/go-yaml/yaml v2.1.0+incompatible
 	github.com/golang/snappy v0.0.0-20170215233205-553a64147049 // indirect
+	github.com/mr-tron/base58 v1.1.2
 	github.com/nspcc-dev/rfc6979 v0.1.0
 	github.com/onsi/gomega v1.4.2 // indirect
 	github.com/pkg/errors v0.8.0

go.sum

@@ -12,6 +12,8 @@ github.com/golang/snappy v0.0.0-20170215233205-553a64147049 h1:K9KHZbXKpGydfDN0a
 github.com/golang/snappy v0.0.0-20170215233205-553a64147049/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
+github.com/mr-tron/base58 v1.1.2 h1:ZEw4I2EgPKDJ2iEw0cNmLB3ROrEmkOtXIkaG7wZg+78=
+github.com/mr-tron/base58 v1.1.2/go.mod h1:BinMc/sQntlIE1frQmRFPUoPA1Zkr8VRgBdjWI2mNwc=
 github.com/nspcc-dev/rfc6979 v0.1.0 h1:Lwg7esRRoyK1Up/IN1vAef1EmvrBeMHeeEkek2fAJ6c=
 github.com/nspcc-dev/rfc6979 v0.1.0/go.mod h1:exhIh1PdpDC5vQmyEsGvc4YDM/lyQp/452QxGq/UEso=
 github.com/onsi/ginkgo v1.6.0 h1:Ix8l273rp3QzYgXSR+c8d1fTG7UPgYkOSELPhiY/YGw=

pkg/crypto/base58.go

@@ -2,88 +2,15 @@ package crypto
 
 import (
 	"bytes"
-	"fmt"
-	"math/big"
 
 	"github.com/CityOfZion/neo-go/pkg/crypto/hash"
+	"github.com/mr-tron/base58"
 	"github.com/pkg/errors"
 )
 
-const prefix rune = '1'
-
-var decodeMap = map[rune]int64{
-	'1': 0, '2': 1, '3': 2, '4': 3, '5': 4,
-	'6': 5, '7': 6, '8': 7, '9': 8, 'A': 9,
-	'B': 10, 'C': 11, 'D': 12, 'E': 13, 'F': 14,
-	'G': 15, 'H': 16, 'J': 17, 'K': 18, 'L': 19,
-	'M': 20, 'N': 21, 'P': 22, 'Q': 23, 'R': 24,
-	'S': 25, 'T': 26, 'U': 27, 'V': 28, 'W': 29,
-	'X': 30, 'Y': 31, 'Z': 32, 'a': 33, 'b': 34,
-	'c': 35, 'd': 36, 'e': 37, 'f': 38, 'g': 39,
-	'h': 40, 'i': 41, 'j': 42, 'k': 43, 'm': 44,
-	'n': 45, 'o': 46, 'p': 47, 'q': 48, 'r': 49,
-	's': 50, 't': 51, 'u': 52, 'v': 53, 'w': 54,
-	'x': 55, 'y': 56, 'z': 57,
-}
-
-// Base58Decode decodes the base58 encoded string.
-func Base58Decode(s string) ([]byte, error) {
-	var (
-		startIndex = 0
-		zero       = 0
-	)
-	for i, c := range s {
-		if c == prefix {
-			zero++
-		} else {
-			startIndex = i
-			break
-		}
-	}
-
-	var (
-		n   = big.NewInt(0)
-		div = big.NewInt(58)
-	)
-	for _, c := range s[startIndex:] {
-		charIndex, ok := decodeMap[c]
-		if !ok {
-			return nil, fmt.Errorf(
-				"invalid character '%c' when decoding this base58 string: '%s'", c, s,
-			)
-		}
-		n.Add(n.Mul(n, div), big.NewInt(charIndex))
-	}
-
-	out := n.Bytes()
-	buf := make([]byte, zero+len(out))
-	copy(buf[zero:], out)
-
-	return buf, nil
-}
-
-// Base58Encode encodes a byte slice to be a base58 encoded string.
-func Base58Encode(bytes []byte) string {
-	var (
-		lookupTable = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"
-		x           = new(big.Int).SetBytes(bytes)
-		r           = new(big.Int)
-		m           = big.NewInt(58)
-		zero        = big.NewInt(0)
-		encoded     string
-	)
-
-	for x.Cmp(zero) > 0 {
-		x.QuoRem(x, m, r)
-		encoded = string(lookupTable[r.Int64()]) + encoded
-	}
-
-	return encoded
-}
-
 // Base58CheckDecode decodes the given string.
 func Base58CheckDecode(s string) (b []byte, err error) {
-	b, err = Base58Decode(s)
+	b, err = base58.Decode(s)
 	if err != nil {
 		return nil, err
 	}
@@ -113,5 +40,5 @@ func Base58CheckDecode(s string) (b []byte, err error) {
 func Base58CheckEncode(b []byte) string {
 	b = append(b, hash.Checksum(b)...)
 
-	return Base58Encode(b)
+	return base58.Encode(b)
 }

pkg/crypto/base58_test.go

@@ -7,26 +7,26 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestBase58Decode(t *testing.T) {
-	input := "1F1tAaz5x1HUXrCNLbtMDqcw6o5GNn4xqX"
+func TestBase58CheckEncodeDecode(t *testing.T) {
+	var b58CsumEncoded = "KxhEDBQyyEFymvfJD96q8stMbJMbZUb6D1PmXqBWZDU2WvbvVs9o"
+	var b58CsumDecodedHex = "802bfe58ab6d9fd575bdc3a624e4825dd2b375d64ac033fbc46ea79dbab4f69a3e01"
 
-	data, err := Base58Decode(input)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	expected := "0099bc78ba577a95a11f1a344d4d2ae55f2f857b989ea5e5e2"
-	actual := hex.EncodeToString(data)
-	assert.Equal(t, expected, actual)
+	b58CsumDecoded, _ := hex.DecodeString(b58CsumDecodedHex)
+	encoded := Base58CheckEncode(b58CsumDecoded)
+	decoded, err := Base58CheckDecode(b58CsumEncoded)
+	assert.Nil(t, err)
+	assert.Equal(t, encoded, b58CsumEncoded)
+	assert.Equal(t, decoded, b58CsumDecoded)
 }
-func TestBase58Encode(t *testing.T) {
-	input := "0099bc78ba577a95a11f1a344d4d2ae55f2f857b989ea5e5e2"
 
-	inputBytes, _ := hex.DecodeString(input)
-
-	data := Base58Encode(inputBytes)
-
-	expected := "F1tAaz5x1HUXrCNLbtMDqcw6o5GNn4xqX" // Removed the 1 as it is not checkEncoding
-	actual := data
-	assert.Equal(t, expected, actual)
+func TestBase58CheckDecodeFailures(t *testing.T) {
+	badbase58 := "BASE%*"
+	_, err := Base58CheckDecode(badbase58)
+	assert.NotNil(t, err)
+	shortbase58 := "THqY"
+	_, err = Base58CheckDecode(shortbase58)
+	assert.NotNil(t, err)
+	badcsum := "KxhEDBQyyEFymvfJD96q8stMbJMbZUb6D1PmXqBWZDU2WvbvVs9A"
+	_, err = Base58CheckDecode(badcsum)
+	assert.NotNil(t, err)
 }

pkg/crypto/keys/publickey.go

@@ -203,11 +203,8 @@ func (p *PublicKey) Address() string {
 	var b = p.Signature()
 
 	b = append([]byte{0x17}, b...)
-	csum := hash.Checksum(b)
-	b = append(b, csum...)
 
-	address := crypto.Base58Encode(b)
-	return address
+	return crypto.Base58CheckEncode(b)
 }
 
 // Verify returns true if the signature is valid and corresponds